In daily life and production, it is often necessary to carry luggage or articles, and trailers are often used during handling. Trailers are widely used for carrying things because of its features of convenient driving, time-saving and labor-saving, many of the prior trailers are composed of a flat plate and are provided with wheels under the flat plate for carrying, this kind of trailers can't be folded and take up a lot when not in use.
There are now some prior trailers that can be folded, but have the following disadvantages:
(1) The trailers have a small capacity, and the heights and volume are increased after folding;
(2) The handle of the trailers can not be automatically reset and is inconvenient to use.